There are numerous pieces of research linking sleep with a handful of vital processes related to health and wellbeing.

According to the US-based Sleep Foundation, sleep is essential to help maintain mood, memory and cognitive performance. It also plays a role in the normal function of the endocrine and immune systems.

But while a lot of vital processes take place during the heaviest stages of sleep, there are benefits to light sleep, too. This means that when you take that quick 20 minute cat nap in the afternoon, you're still doing wonders for your health.